Danny Boyle has said he is planning a sequel to Trainspotting that could find its way to the big screen for 2016, the 20th anniversary of the cult film about Edinburgh drug addicts.

Speaking to the Playlist while promoting his new film Trance, Boyle said that Trainspotting screenwriter John Hodge was working on an adaptation of Porno, Irvine Welsh's 2002 sequel to his late-80s-set debut. The long-mooted film adaptation would reunite Renton, Sick Boy and Begbie two decades on.

"This has been a long time coming," said Boyle. "There's always been this long-term plan for Trainspotting 2. If John can produce a decent enough script, I don't think there will be any barriers to Ewan [McGregor] or any of the cast coming back. I think they'll wanna know that the parts are good so they don't feel like they are letting anyone down."

Boyle added: "The reason for doing it again is that people cherish the original, people remember it or have caught up with it if they never saw because they were younger. So you want to make sure you don't disappoint people. That will be the only criteria I think."

The Oscar-winning British film-maker said the new project would only be "very loosely based" on the novel Porno, which he has previously described as being "not as good" as Trainspotting. "There's a couple of things that are based on the book, but obviously we'd have to have Irvine on board," he said. "The ideal time would be Porno in 2016, because it was 1996 when Trainspotting came out. Twenty years, it's like, 'wow, where did that go?'"

Porno sees Renton, Sick Boy and Begbie, along with the hapless Spud, becoming embroiled in a scheme to raise cash by making a pornographic movie. McGregor, Robert Carlyle, Jonny Lee Miller and Ewan Bremner would all be expected to return. The book also features Diane Coulston, played in Trainspotting by Kelly Macdonald.

Boyle's comments suggest he and McGregor have made up following their falling out over The Beach. The director cast Leonardo DiCaprio in the lead role of the 2000 film. However, he had allegedly discussed filming dates with McGregor, with whom he had previously worked on Shallow Grave, Trainspotting and A Life Less Ordinary. "They absolutely made me think that I was playing the character in The Beach," McGregor told the Times in 2011. "All the while they were keeping me there just in case Leonardo pulled out – which is really nasty."

Trainspotting, the saga of a bunch of junkies cutting a swath through Edinburgh, became an instant classic of British cinema. Nearly 20 years later, director Danny Boyle talks to Hibrow about what inspired him